REVIEW 4 major objections 5 minor 24 references
How to Achieve Higher Accuracy with Less Training Points?
T0 review · 4 major / 5 minor · reviewed 2026-08-16 · deepseek-v4-flash
Pith's one-line read Selecting training points by their influence on validation predictions lets a logistic regression model match full-data test accuracy with 10% of the extra data and exceed it with 60%.
desk verdict The paper's '10% of the data' claim is actually 64% of the full training set, but the underlying influence-based selection idea is coherent and worth a quick look. read the letter →
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
The reading
What carries the argument
The mechanism is the influence function applied to adding, rather than removing, training points. Using the Hessian of the empirical risk at the fitted parameters, Equation (4) approximates the parameter change from adding a subset, and Equation (5) translates that change into predicted output changes on validation points. Each candidate point is scored by summing the predicted changes aligned with moving each validation prediction toward its correct label, with variants that weight by label discrepancy, threshold, top-K prioritization, flip counts, or misalignment penalties. Positively scored points form the subset that is added and the model is retrained.
What would settle it
Train the model on the exact 60% subset selected by Method 1 and evaluate on the held-out test set; if the test accuracy does not exceed the 0.627 of the Add-Full baseline, the reported advantage does not reproduce. Separately, compute the per-candidate influence scores from Equation (4)-(5), retrain the model adding each single candidate alone, and compare the rank correlation between predicted and actual validation accuracy changes; a weak or negative correlation for high-scoring candidates would show the linearized ranking is not what carries the result.
Extended reading notes
Core claim
The central claim is that the influence of adding a training point on validation predictions, computed through a linearized influence-function approximation (IP-adding), provides a usable ranking for selecting a small subset of additional training data. On a binarized movie-review sentiment dataset with a logistic regression model, selecting the top few percent of additional examples by cumulative positive influence yields 0.630 test accuracy at 10% of the pool, above the 0.627 of training on the full pool; selecting 60% by the simplest variant (Method 1) yields 0.644, the highest reported. The authors interpret this as evidence that comparable or superior accuracy is achievable with a fraction of the training data.
Load-bearing premise
The influence ranking is computed with a linear approximation around the original model's parameters, and the paper assumes that ranking remains correct even when the added subset is large enough (60% of the pool, on the order of a thousand points) to move the optimum far from the linearization point and create interactions among the added points.
Editorial extensions
If this is right
- Subset selection by influence can replace full-data training: 10% of the additional pool gives comparable test accuracy to using 100% (0.630 vs 0.627).
- Using a larger selected fraction, 60%, can improve accuracy relative to full-data training (0.644 vs 0.627).
- Random selection underperforms both full-data training and influence-based selection, showing that which points are added matters, not just how many.
- The scoring rule is evaluated on a validation set and requires no retraining for each candidate, making the selection step cheap relative to exhaustive search.
- The heuristic variants trade off fraction selected against accuracy, and the simplest variant (Method 1) gives the best test accuracy at 60%.
Reading between the lines
- The linearized influence approximation is only tested implicitly; directly comparing the predicted ranking against per-point retraining effects would reveal how much ranking quality degrades as the selected subset grows, especially at 60% of the pool.
- Because selection is done once at the original parameters, the approach resembles a single-step active-learning procedure; iterating the selection with retraining between rounds could further reduce the required fraction, but that is an extension the paper does not test.
- The validation set stands in for the test distribution, so the method's practical value depends on how well that proxy holds; under distribution shift, the selected points may be the wrong ones.
- The same addition-based influence score could apply to other convex models or to mini-batch selection in neural networks, though Hessian-based approximations become more delicate there.
Signed reviews
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper proposes influence-function-based heuristics for selecting a subset of additional training points to add to an existing logistic-regression model for binary classification. The authors derive an IP-adding approximation for the change in test predictions when a set S of samples is added, then propose six heuristic selection methods. In experiments on a binarized Stanford Sentiment Treebank, they report that Method 3, which selects 10% of the additional pool, achieves test accuracy comparable to training on all data, and that Method 1, which selects 60% of the additional pool, achieves higher accuracy than full-data training. The abstract and conclusion restate these results as achieving comparable accuracy with "only 10% of the data" and better accuracy with "60% of the data."
Significance. If the empirical claims were as stated, the work would provide a practical data-selection strategy that substantially reduces training cost while preserving or even improving accuracy. The influence-function formalism is standard and the evaluation uses a held-out test set, not the validation set used for selection, so the core comparison is not circular. However, the headline claims are not supported by the experimental design as written: the 10% and 60% figures refer to the additional pool, not the total training set. Moreover, the validity of the influence approximation for the large added subsets is untested, and the random baseline is not reported on the test set. The paper's contribution is currently a collection of heuristics with preliminary evidence, not a demonstrated reduction in total training data.
major comments (4)
- [Abstract and Section 5.1, Table 1] The central quantitative claim is misstated. In Section 5.1 the original training set Ztr has 4,152 points and the additional pool Ztr' has 2,768 points, so full-data training uses 6,920 points. Method 3 selects 10% of Ztr' (about 277 points), giving a total training set of 4,429 points, which is 64% of the full dataset, not 10%. Method 1 selects 60% of Ztr' (about 1,661 points), giving 5,813 points, which is 84% of the full dataset, not 60%. The 'Added Percentage' column in Table 1 explicitly refers to the additional pool, and the abstract and conclusion inherit that number without the qualifier. Please rephrase the claims to state the fraction of the additional pool and the corresponding fraction of the total data, and add baselines trained on the same total number of points sampled from scratch to support any claim about total-data efficiency.
- [Section 3.1, Eqs. (4)-(5)] The influence approximation in Eqs. (4)-(5) is a first-order expansion around the original parameters \w^c and ignores interactions among the added points. For Method 1, the added subset is 60% of Ztr' (1,661 points), and for Method 3 it is 277 points. With such large subsets, retraining moves the optimum far from the linearization point, so the ranking produced by the approximation may not reflect the true effect of adding the points. The paper does not report any validation of the approximation, such as a correlation between the IP-adding scores and the actual accuracy changes measured by retraining on small subsets, or a comparison of one-shot selection versus iterative/alternating selection. Please add such an experiment or clearly restrict the claims to the regime where the linearization is justified.
- [Section 5.2 and Table 1] The random baseline is incompletely reported and the comparison to it is unsupported. Table 1 has a 'Random Val Acc' column but no corresponding 'Random Test Acc' column, yet the text states that 'on average, the random selection strategy results in a 3% performance drop compared to our proposed selection mechanisms.' Without a random-selection test accuracy and without variance estimates across multiple random draws and multiple training runs, the claim that the method outperforms random selection is not demonstrated. Please report test accuracy for random selection (with standard errors over seeds) and for the proposed methods across multiple runs.
- [Section 5.2 and Table 1] The paper compares six heuristic variants and highlights the best-performing ones (Method 1 at 60% and Method 3 at 10%). Because the variants were selected after seeing validation accuracy, the reported test numbers may reflect selection among six heuristics on the validation set rather than a single prespecified method. This is a multiple-comparisons concern. The authors should either prespecify one method or report results for all variants with a correction for the number of comparisons, at minimum by disclosing that the best result was chosen from six variants.
minor comments (5)
- [Section 1] The phrase 'statical perspective' appears to be a typo for 'statistical perspective'.
- [Section 3.1, Eq. (4)] Equation (4) has an unmatched parenthesis in the term \(\frac{1}{N}\sum_{z_i \in S}\nabla_w L(z_i,w))\). Please correct the notation.
- [Section 4, Algorithm 1] The algorithm description uses 'test point' and 'validation point' interchangeably; the pseudocode computes \Delta f over Zval, while the text sometimes refers to a test point xt. Please make the roles of the validation set and test set consistent throughout.
- [Section 5.1] No hyperparameter values (e.g., the regularization strength \lambda, the threshold \tau, or the feature dimensionality after bag-of-words) are reported, which prevents reproduction. Please include these details.
- [Section 5.2, Table 1] The table caption is missing a period at the end of the caption text.
Circularity Check
No significant circularity; the empirical claim is test-set evaluated, though the headline '10%/60%' percentages are relative to the additional pool only.
full rationale
I traced the claimed derivation chain: Eq. (1)-(3) define the training objective and the retrained model; Eq. (4)-(5) are the standard first-order influence-function approximation using the Hessian and gradient at the original optimum. The selection rules in Section 4 (Methods 1-6 and Algorithm 1) compute scores from the original model, the additional pool Ztr', and the validation set Zval. The test set is held out and is never used to fit any score, threshold, or hyperparameter. The reported accuracies in Table 1 come from retraining logistic regression on the selected subsets and evaluating on that held-out test set, so the central empirical claim is not circular: the influence scores are textbook quantities, and the selection does not encode the test outcome by construction. The only notable concern is a reporting mismatch, not circularity: the abstract and Section 6 state 'using only 10% of the data' and '60% of the dataset,' whereas Table 1's 'Added Percentage' is the percentage of the additional pool Ztr' (2,768 points). With the original 4,152 points, Method 3 actually trains on about 64% of the full 6,920-point data, and Method 1 on about 84%. This overstates the data reduction, but it is an accuracy/interpretation issue rather than a self-referential derivation. The self-citations [15,16] are background literature on prediction flipping and are not load-bearing for the selection method or the empirical result. I therefore find no circular step and assign score 0.
Assumptions & free parameters
free parameters (3)
- Method 3 top-K fraction =
0.10
- Regularization strength lambda =
not reported
- Weights in Method 2 and Method 5 =
unspecified
assumptions (3)
- standard math R(w) is twice differentiable and strongly convex, as assumed in Eq. (1)-(2).
- domain assumption The validation set distribution is similar to the test set distribution.
- domain assumption The infinitesimal influence linearization in Eq. (4)-(5) remains accurate for finite, large additions of up to 60% of the extra pool.
Cite this review
Pith. "Pith review of How to Achieve Higher Accuracy with Less Training Points?." pith.science (2026). https://pith.science/paper/GBM3GG3B
@misc{pith2026250413586,
author = {Pith},
title = {Pith review of: How to Achieve Higher Accuracy with Less Training Points?},
year = {2026},
howpublished = {\url{https://pith.science/paper/GBM3GG3B}},
note = {Machine review of arXiv:2504.13586}
}
read the original abstract
In the era of large-scale model training, the extensive use of available datasets has resulted in significant computational inefficiencies. To tackle this issue, we explore methods for identifying informative subsets of training data that can achieve comparable or even superior model performance. We propose a technique based on influence functions to determine which training samples should be included in the training set. We conducted empirical evaluations of our method on binary classification tasks utilizing logistic regression models. Our approach demonstrates performance comparable to that of training on the entire dataset while using only 10% of the data. Furthermore, we found that our method achieved even higher accuracy when trained with just 60% of the data.
Reference graph
Works this paper leans on
-
[1]
T. Ahmad, R. Madonski, D. Zhang, C. Huang, and A. Mujeeb, “Data-driven probabilistic machine learn- ing in sustainable smart energy/smart energy systems: Key developments, challenges, and future research op- portunities in the context of smart grid paradigm,” Re- newable and Sustainable Energy Reviews, vol. 160, p. 112128, 2022. 1
work page 2022
- [2]
-
[3]
A systematic review of green ai,
R. V erdecchia, J. Sallou, and L. Cruz, “A systematic review of green ai,” Wiley Interdisciplinary Reviews: Data Mining and Knowledge Discovery, vol. 13, no. 4, p. e1507, 2023
work page 2023
-
[4]
Toward green ai: A methodological survey of the scientific literature,
E. Barbierato and A. Gatti, “Toward green ai: A methodological survey of the scientific literature,” IEEE Access, vol. 12, pp. 23 989–24 013, 2024. 1
work page 2024
-
[5]
An empirical comparison of instance attribution methods for nlp,
P . Pezeshkpour, S. Jain, B. C. Wallace, and S. Singh, “An empirical comparison of instance attribution methods for nlp,” arXiv preprint arXiv:2104.04128 , 2021. 1
arXiv 2021
-
[6]
Iaeval: A comprehensive evaluation of in- stance attribution on natural language understanding,
P . Gu, Y . Shen, L. Wang, Q. Wang, H. Wu, and Z. Mao, “Iaeval: A comprehensive evaluation of in- stance attribution on natural language understanding,” in Findings of the Association for Computational Lin- guistics: EMNLP 2023 , 2023, pp. 11 966–11 977. 1
work page 2023
-
[7]
Machine learning explainability in finance: an application to default risk analysis,
P . Bracke, A. Datta, C. Jung, and S. Sen, “Machine learning explainability in finance: an application to default risk analysis,” 2019. 1
work page 2019
-
[8]
T. Broderick, R. Giordano, and R. Meager, “An au- tomatic finite-sample robustness metric: When can dropping a little data make a big difference?” arXiv preprint arXiv:2011.14999, 2020. 2
arXiv 2011
Show all 24 references
-
[9]
Explainable machine learning for pub- lic policy: Use cases, gaps, and research directions,
K. Amarasinghe, K. T. Rodolfa, H. Lamba, and R. Ghani, “Explainable machine learning for pub- lic policy: Use cases, gaps, and research directions,” Data & Policy, vol. 5, p. e5, 2023. 1
2023
-
[10]
Understanding black-box predictions via influence functions,
P . W . Koh and P . Liang, “Understanding black-box predictions via influence functions,” in International conference on machine learning . PMLR, 2017, pp. 1885–1894. 1, 2
2017
-
[11]
De- bugging tests for model explanations,
J. Adebayo, M. Muelly, I. Liccardi, and B. Kim, “De- bugging tests for model explanations,” arXiv preprint arXiv:2011.05429, 2020. 2
2011 arXiv
-
[12]
Explain- ing black box predictions and unveiling data ar- tifacts through influence functions,
X. Han, B. C. Wallace, and Y . Tsvetkov, “Explain- ing black box predictions and unveiling data ar- tifacts through influence functions,” arXiv preprint arXiv:2005.06676, 2020
2005 arXiv
-
[13]
Interactive label cleaning with example- based explanations,
S. Teso, A. Bontempelli, F. Giunchiglia, and A. Passerini, “Interactive label cleaning with example- based explanations,” Advances in Neural Information Processing Systems, vol. 34, pp. 12 966–12 977, 2021. 1, 2
2021
-
[14]
R. D. Cook and S. Weisberg, Residuals and influence in regression. New Y ork: Chapman and Hall, 1982. 1, 2
1982
-
[15]
How many and which training points would need to be removed to flip this prediction?
J. Y ang, S. Jain, and B. C. Wallace, “How many and which training points would need to be removed to flip this prediction?” in Proceedings of the 17th Conference of the European Chapter of the Association for Computational Linguistics , A. Vlachos and I. Augenstein, Eds. Dubro...
2023
-
[16]
Relabeling minimal training subset to flip a prediction,
J. Y ang, L. Xu, and L. Y u, “Relabeling minimal training subset to flip a prediction,” in Findings of the Association for Computational Linguistics: EACL 2024, Y . Graham and M. Purver, Eds. St. Julian’s, Malta: Association for Computational Linguistics, Mar. 2024, pp. 1085–10...
2024
-
[17]
The influence curve and its role in ro- bust estimation,
F. R. Hampel, “The influence curve and its role in ro- bust estimation,” Journal of the american statistical association, vol. 69, no. 346, pp. 383–393, 1974. 2
1974
-
[18]
Characterizations of an empirical influence function for detecting influential cases in regression,
R. D. Cook and S. Weisberg, “Characterizations of an empirical influence function for detecting influential cases in regression,” T echnometrics, vol. 22, no. 4, pp. 495–508, 1980. 2
1980
-
[19]
Machine unlearning of features and labels,
A. Warnecke, L. Pirch, C. Wressnegger, and K. Rieck, “Machine unlearning of features and labels,” arXiv preprint arXiv:2108.11577, 2021. 2
2021 arXiv
-
[20]
Resolving training biases via influence-based data relabeling,
S. Kong, Y . Shen, and L. Huang, “Resolving training biases via influence-based data relabeling,” in Interna- tional Conference on Learning Representations, 2021. 2
2021
-
[21]
Datamodels: Understanding predictions with data and data with predictions,
A. Ilyas, S. M. Park, L. Engstrom, G. Leclerc, and A. Madry, “Datamodels: Understanding predictions with data and data with predictions,” in Proceedings of the 39th International Conference on Machine Learn- ing, ser. Proceedings of Machine Learning Research, K. Chaudhuri, S. ...
2022
-
[22]
Minimal explanations for neural network predictions,
O. E. Harzli, B. C. Grau, and I. Horrocks, “Minimal explanations for neural network predictions,” arXiv preprint arXiv:2205.09901, 2022. 2
2022 arXiv
-
[23]
Learn- ing the difference that makes a difference with counterfactually-augmented data,
D. Kaushik, E. Hovy, and Z. C. Lipton, “Learn- ing the difference that makes a difference with counterfactually-augmented data,” arXiv preprint arXiv:1909.12434, 2019. 2
1909 arXiv
-
[24]
Recursive deep models for semantic compositionality over a sentiment tree- bank,
R. Socher, A. Perelygin, J. Wu, J. Chuang, C. D. Man- ning, A. Y . Ng, and C. Potts, “Recursive deep models for semantic compositionality over a sentiment tree- bank,” in Proceedings of the 2013 conference on em- pirical methods in natural language processing, 2013, pp. 1631–1642. 4
2013
Reviewed August 16, 2026 · model on record in the stance chip above.
Discussion (0). Continue with ORCID to comment.